The accurate measurement of blood pressure (BP) is essential for the diagnosis and management of hypertension. Restricted use of mercury devices, increased use of oscillometric devices, discrepancies between clinic and out-of-clinic BP, and concerns about measurement error with manual BP measurement techniques have resulted in uncertainty for clinicians and researchers. The National Heart, Lung, and Blood Institute of the U.S. National Institutes of Health convened a working group of clinicians and researchers in October 2017 to review data on BP assessment among adults in clinical practice and clinic-based research. In this report, the authors review the topics discussed during a 2-day meeting including the current state of knowledge on BP assessment in clinical practice and clinic-based research, knowledge gaps pertaining to current BP assessment methods, research and clinical needs to improve BP assessment, and the strengths and limitations of using BP obtained in clinical practice for research and quality improvement activities.

There is increasing interest in unattended automated office blood pressure (OBP) measurement, which gives lower blood pressure values than the conventional auscultatory OBP. Whether unattended automated OBP differs from standardized attended automated OBP performed using the same device and measurement protocol remains uncertain. A systematic review and meta-analysis of studies (aggregate data) comparing unattended vs attended automated OBP using the same device and measurement protocol (conditions, number of measurements, visits) was performed. Ten eligible studies (n = 1004, weighted age 60.8 ± 4.2 [SD] years, 55% males) were analyzed. Unattended OBP (pooled systolic/diastolic 133.9 [95% CI: 129.7, 138]/80.6 [95% CI: 77, 84.2] mm Hg) did not differ from attended OBP (135.3 [95% CI: 130.9, 139.6]/81 [95% CI: 77.6, 84.3] mm Hg); pooled systolic OBP difference -1.3, 95% CI: -4.3, 1.7 mm Hg and diastolic -0.4, 95% CI: -1.2, 0.3 mm Hg. Nine of ten studies achieved high quality score and no publication bias was identified. Meta-regression analysis did not reveal any effect of age, gender, or attended systolic OBP on the unattended-attended systolic OBP difference (P = NS for all). However, there was a trend toward higher attended than unattended OBP at higher OBP levels. These data suggest that, when the same device and measurement protocol are used, attended automated OBP provides similar blood pressure values as unattended automated OBP. Although unattended automated OBP is theoretically advantageous as it ensures that standardized conditions and measurement protocol are used, attended automated OBP, if carefully performed, appears to be a reasonable and practical alternative.

The measurement of blood pressure in the office (OBP) remains the basis for hypertension diagnosis and management for more than half a century. Despite the increasing use of out-of-office blood pressure measurement using home and less so ambulatory monitoring and their endorsement by hypertension societies, at present and for some time to come it is likely that in many people the diagnosis and management of hypertension will be based on OBP measurement alone. OBP measurement is a very variable method affected by multiple factors, which have major impact on the OBP level, reproducibility and prognostic ability. Thus, there are several types of OBP measurement, depending on the device type, conditions, observer's presence and the number of readings. The 4 main OBP types are: Type I: Auscultatory OBP in clinical practice; Type II: Automated attended OBP in clinical practice; Type III: Research setting OBP; Type IV: Unattended automated OBP. These OBP types have different standardization level, different reproducibility, different clinical relevance and different thresholds for hypertension diagnosis. Unless the methodological details of OBP measurement are reported, any conclusions based on such measurements in clinical research and in practice are questionable.

: Studies using ambulatory blood pressure (BP) monitoring have shown that BP during night-time sleep is a stronger predictor of cardiovascular outcomes than daytime ambulatory or conventional office BP. However, night-time ambulatory BP recordings may interfere with sleep quality because of the device cuff inflation and frequency of measurements. Hence, there is an unmet need for obtaining high quality BP values during sleep. In the last two decades, technological development of home BP devices enabled automated BP measurements during night-time. Preliminary data suggest that nocturnal home BP measurements yield similar BP values and show good agreement in detecting nondippers when compared with ambulatory BP monitoring. Thus, nocturnal home BP measurements might be a reliable and practical alternative to ambulatory BP monitoring to evaluate BP during sleep. As the use of home BP devices is widespread, well accepted by users and has relatively low cost, it may prove to be more feasible and widely available for routine clinical assessment of nocturnal BP. At present, however, data on the prognostic relevance of nocturnal BP measured by home devices, the optimal measurement schedule, and other methodological issues are lacking and await further investigation. This article offers a systematic review of the current evidence on nocturnal home BP, highlights the remaining research questions, and provides preliminary recommendations for application of this novel approach in BP management.

The 2017 US guidelines for pediatric hypertension place considerable emphasis on blood pressure measurements, which are the cornerstone for hypertension diagnosis and management. It is recognized that when the diagnosis of hypertension is based solely on office blood pressure measurements, many children are misclassified (over- or underdiagnosed). Therefore, out-of-office blood pressure evaluations using ambulatory or home blood pressure monitoring are often necessary to obtain an accurate diagnosis. Strong evidence for the diagnostic and clinical value of ambulatory blood pressure monitoring in children has justified its central role in decision making in recent pediatric recommendations. However, ambulatory blood pressure monitoring is not widely accessible in primary care. There is little evidence for home blood pressure monitoring in children, yet this method is widely available and feasible for the evaluation of elevated blood pressure in children. This article presents a case for using home blood pressure monitoring for the management of children with suspected or treated hypertension in clinical practice in comparison to using office measurements or ambulatory blood pressure monitoring, as well as its optimal application. More research on home blood pressure monitoring in children is urgently needed.

Hypertension is now recognized as a major global cause of morbidity and death. All decisions relating to the epidemiology, diagnosis, and management of hypertension are dependent on being able to measure blood pressure accurately. Scientists have developed protocols to assess the accuracy of blood pressure-measuring devices, but little attention has been given to informing users which devices are accurate and inaccurate. This article identifies a recipient audience of researchers, clinicians, and scientists, the public, healthcare executives and administrators, and consumer and regulatory bodies, and discusses how best to communicate the results of device accuracy to these groups with the aim of improving the accurate measurement of blood pressure.

According to the established validation protocols, a typical validation study of a blood pressure (BP) monitor includes general population adults with normal or elevated BP. It is recognized, however, that the automated (oscillometric) BP monitors may have different accuracy or uses in some special populations compared with adults in the general population. Thus, an automated BP monitor with proven accuracy in a general population of adults may not be accurate in a special population, and therefore separate validation is needed. Recognized special populations deserving separate validation are those for which there is theoretical, and also clinical evidence, that the accuracy of BP monitors in these groups differs from that in the general population. Young children, pregnant women (including those with preeclampsia), individuals with arm circumference >42 cm, and patients with atrial fibrillation are regarded as special populations. Adolescents, individuals older than 80 years, and patients with end-stage renal disease or diabetes mellitus have also been considered as possible special groups, but there is still inadequate evidence of altered accuracy of BP monitors in these subjects. Validation studies should be performed in special populations and evaluated separately after the BP-measuring device has successfully undergone a validation study in a general population (unless the test device is intended only for a special population). This article discusses issues relating to the measurement of BP and the diagnosis of hypertension in selected special populations, as well as in low-resource settings, where a simplified yet efficient evaluation strategy is necessary.

Blood pressure variability is an entity that characterizes the continuous and dynamic fluctuations that occur in blood pressure levels throughout a lifetime. This phenomenon has a complex and yet not fully understood physiological background and can be evaluated over time spans ranging from seconds to years. The present paper provides a short overview of methodological aspects, clinical relevance, and potential therapeutic interventions related to the management of blood pressure variability.

The accuracy of blood pressure (BP) measuring devices is fundamental to good practice and scientific research. International guidelines on BP measurement are provided for clinicians who diagnose and treat patients with hypertension, clinical researchers who conduct trials on the efficacy of BP lowering drugs and interventional strategies, epidemiologists who conduct population surveys to determine the demographic consequences of hypertension on society, and researchers who perform meta-analyses on published research to further influence the practice of medicine and the provision of resources. Although the outcomes of the endeavors of all these groups are dependent on the accuracy of BP measurements, the equipment is often of doubtful accuracy and the methodology of measurement is often poorly described and frequently not standardized. Thus, the fundamental element of hypertension evaluation has been largely ignored by both clinical practitioners and scientific researchers. Here, the authors briefly review the development of efforts to improve and validate the accuracy of BP measuring devices and highlight the deficiencies that persist. We conclude that, to protect the public from the serious consequences of inaccurate BP measurements, the following steps are required: (1) regulatory requirement for mandatory independent validation of all BP measuring devices using a universal protocol; (2) accreditation of laboratories for the performance of BP device validations; (3) online evaluation of validation studies with detection of protocol violations prior to publication of results; and (4) establishment of an independent scientific forum for the listing of accurate BP measuring devices.

A summary of statements for blood pressure (BP) measurement in the evaluation of hypertension in the 21st century by 25 international experts is provided. The status of office, home and ambulatory BP measurement techniques are discussed. Office BP measurement, whether automated (preferred), or otherwise, should only be used as a screening measurement, and diagnostic decisions for the initiation and titration of drug treatment should be based on out-of-office measurements (ambulatory or home). The hardware and software requirements and the adaptations of BP measuring devices to record other cardiovascular functions, such as arrhythmias, and adaptations for smartphone use and for electronic transmission are discussed. Regulatory bodies are urged to make accuracy and performance assessment mandatory before marketing BP measuring devices. The legal implications of manufacturing inaccurate devices are noted.

Blood pressure (BP) is a vital sign and the essential measurement for the diagnosis of hypertension. Therefore, its accurate measurement is a key element for the evaluation of many medical conditions and for the reliable diagnosis and efficient treatment of hypertension. In the last 3 decades prestigious organizations, such as the US Association for the Advancement of Medical Instrumentation (AAMI), the British Hypertension Society, the European Society of Hypertension (ESH) Working Group on BP Monitoring, and the International Organization for Standardization (ISO), have developed protocols for clinical validation of BP measuring devices. All these initiatives aim to standardize validation procedures and establish minimum accuracy standards for BP monitors. Unfortunately, only a few of the BP measuring devices available on the market have been subjected to independent validation using one of these protocols. Recently, the AAMI, ESH, and ISO experts agreed to develop a single universally acceptable standard (AAMI/ESH/ISO), which will replace all previous protocols. This major international initiative has been undertaken to best serve the needs of patients with hypertension, a public interested in cardiovascular health, practicing physicians, scientific researchers, regulatory bodies, and manufacturers. There is an urgent need to influence regulatory authorities throughout the world to make it mandatory for all BP measuring devices to have undergone independent validation before approval for marketing. Efforts need to be intensified to improve the accuracy of BP measuring devices, further optimize the validation procedure, and ensure that objective and unbiased validation data become available.

In the last 2 decades, several scientific societies have published specific guidelines for blood pressure (BP) measurement, providing detailed recommendations for office, home, and ambulatory BP monitoring. These documents typically provided strong support for using out-of-office BP monitoring (ambulatory and home). More recently, several organizations recommended out-of-office BP evaluation as a primary method for diagnosing hypertension and for treatment titration, with office BP regarded as a screening method. Efforts should now be directed towards making ambulatory and home BP monitoring readily available in primary care and ensuring that such measurements are obtained by following current guidelines. Moreover, it should be mandatory for all published clinical research papers on hypertension to provide details on the methodology of the BP measurement.

Home blood pressure monitoring provides multiple measurements in the usual environment of each individual, allows the detection of intermediate hypertension phenotypes (white-coat and masked hypertension), and appears to have superior prognostic value compared to the conventional office blood pressure measurements. Accumulating evidence suggests that home blood pressure monitoring improves long-term hypertension control rates. Moreover, it is widely available, relatively inexpensive, and well accepted by patients. Thus, current guidelines recommend home blood pressure monitoring as an essential method for the evaluation of almost all untreated and treated patients with suspected or treated hypertension. Validated automated upper-arm cuff devices with automated storage and averaging of readings should be used. The home blood pressure monitoring schedule for 4 to 7 days with exclusion of the first day (12-24 readings) should be averaged to provide values for decision making.